Alternative Fuel Excise Tax
Alternative fuels are taxed equal to the motor fuel tax on a gallon equivalent basis. Alternative fuels include natural gas, propane, hydrogen, and hythane. A gallon equivalent is defined as 5.660 pounds (lbs.) of compressed natural gas, 6.06 lbs. of liquefied natural gas, 480.11 standard cubic feet of hydrogen, and 162.44 standard cubic feet of hydrogen compressed natural gas. A gallon of propane is measured as 4 quarts or 3.785 liters.